Porcelain-fused-to-metal (PFM) dental crowns were used as a technological stopgap when people were beginning to realize just how important it was to have attractive dental restorations but ceramics weren’t yet strong enough to fulfill the role. A thin layer of porcelain was bonded to a metal substructure, hoping for the best of both worlds: a crown that was strong as metal and as attractive as ceramic.
But the reality was often that it was neither. Because the porcelain wasn’t strong enough to hold up in many of the situations where these crowns were employed, it often cracked and broke off. Sometimes, it would just flake off in places where it wasn’t even being subjected to force. And the metal underneath was not designed to stand up on its own, so it could wear away once exposed, putting the tooth at risk.
So if you had a PFM crown, it’s not surprising that you’re now looking to replace it. As you look around at the options, you might be trying to decide whether you should go the ceramic direction or the metal one.
Benefits of Metal Crowns
There are certainly some benefits of metal crowns that should be named. They are really very durable, and they’re easy on the opposing teeth. And if you get the noble metal crowns, they are chemically inert so they’re generally not harmful.
However, there are some disadvantages of metal crowns. If you opted for a PFM crown, then it probably matters to you how your smile looks, so there’s the obvious problem with metal crowns being highly visible, even if they’re in the back of the mouth. And there’s the problem that you will likely experience more temperature sensitivity with a metal crown than you did with a PFM crown. Finally, there’s the fact that some metal crowns are made with alloys that can be less healthy. Nickel is a common metal used in non-noble crowns, and it’s also one of the most common allergens. If can cause significant irritation if you get a crown with nickel in it and turn out to be allergic. And even if you aren’t allergic to the metal, non-noble crowns can lead to discoloration in your gums, the same way that cheap jewelry can cause your skin to turn green.
Benefits of All-Porcelain Crowns
Really, porcelain crowns are the best option for replacing PFM crowns. Where ceramics didn’t used to be strong enough to handle the bite force in your back teeth (molars), these days ceramics are strong enough to handle it and more. For all intents and purposes, they are as strong as metal crowns. They also look highly attractive, with the color, translucency, and luster of natural teeth. And they insulate you against temperature better than metal crowns. Perhaps most importantly, they’re wholly biocompatible–there’s no concern about adverse reactions to the material.
But there are some disadvantages of all-porcelain crowns. They can be more expensive than metal crowns, and you might need to have more tooth material removed to make room for a ceramic crown.
If you would like to talk about the best replacement for your damaged or lost PFM crown, please call